Does corneal epithelial thickness show the severity of psoriasis? SD-OCT study

Abstract Background Previous studies have generally focused on dry eye test abnormalities and ocular involvements such as uveitis, and blepharitis in psoriasis. Psoriasis area severity ındex (PASI), which is used to assess psoriasis severity, is a time-consuming and complex tool. Objective To evaluate the relationship between disease severity and central corneal epithelial thickness (CCET) in psoriasis. Methods 175 eyes of 175 psoriasis patients and 57 eyes of 57 healthy individuals as a control group was included in this study. Psoriasis patients were divided into three subgroups according to PASI score as < 10 mild, 10‒20 moderate and > 20 severe. CCET was measured by spectral domain-optical coherence tomography (SD-OCT), and mean values were recorded. Mean CCET values were compared between the psoriasis groups and the control group. Additionally, the relationship between PASI score and CCET was examined. Results The mean CCET value was 58.06 ± 3.1 μm in the mild group, 60.10 ± 5.0 μm in the moderate group, 65.75 ± 6.3 μm in the severe group and 56.16 ± 3.1 μm in the control group. It was determined that the mean CCET value was significantly higher in all psoriasis groups compared to the control group (p < 0.001). The mean CCET value was significantly higher in the moderate psoriasis group than in the mild psoriasis group (p = 0.018), and in the severe psoriasis group compared to the moderate psoriasis group (p < 0.001). There was a strong positive correlation between PASI score and CCET (p < 0.001, r = 0.519). Study limitations Cross-sectional design and a relatively small number of participants. Conclusions There is a strong positive correlation between psoriasis severity and CCET. Contactless measurement of CCET by SD-OCT can be an indicator of psoriasis severity.

Evaluation of the impact of subepithelial corneal infiltrates on corneal biomechanics after epidemic keratoconjunctivitis / Avaliação do impacto de infiltrados sub-epiteliais corneanos na biomecânica corneana após ceratoconjuntivite epidêmica

ABSTRACT Purpose: To examine the effect of subepithelial corneal infiltrates on corneal biomechanical properties after epidemic keratoconjunctivitis compared to that in healthy controls. Methods: The cross-sectional study included consecutive patients with bilateral subepithelial corneal infiltrates after epidemic keratoconjunctivitis and healthy controls. Best corrected visual acuity corneal subepithelial infiltrate scoring Fantes grading scale, and central corneal thickness were measured. Corneal hysteresis corneal resistance factor Goldmann correlated intraocular pressure and corneal compensated intraocular pressure were assessed using an ocular response analyzer. Results: This study included 66 eyes of 33 patients with subepithelial corneal infiltrates following epidemic keratoconjunctivitis and randomly selected 37 eyes of 37 healthy volunteers. The mean Fantes and CSIS scores were 1.8 ± 0.8 and 2.9 ± 1.3, respectively, in the first involved eyes and 1.3 ± 1.1 and 1.9 ± 1.7, respectively, in the fellow eyes (p=0.009 and p=0.002, respectively). The first (526.1 ± 28.1 µm; p=0.005) and second involved eyes (523.4 ± 38.1 µm; p=0.044) had significantly thinner corneas compared to that in healthy controls (557.0 ± 38.1 µm). While best-corrected visual acuity showed a positive correlation with corneal resistance factor (r=0.363, p=0.045) and corneal hysteresis (r=0.414, p=0.021), corneal subepithelial infiltrate scoring showed a negative correlation with Goldmann correlated intraocular pressure (r=-0.479, p=0.006) and corneal compensated intraocular pressure (r=-0.413, p=0.021). Conclusion: Eyes with subepithelial corneal infiltrates had significantly thinner corneas compared to that in healthy controls. A positive correlation of the corneal resistance factor and corneal hysteresis with best-corrected visual acuity and a negative correlation of the Goldmann correlated intraocular pressure and corneal compensated intraocular pressure with corneal subepithelial infiltrate scoring should be taken into account when measuring intraocular pressure values in patients with subepithelial corneal infiltrates.

RESUMO Objetivo: Examinar o efeito de infiltrados sub-epiteliais corneanos nas propriedades biomecânicas da córnea após ceratoconjuntivite epidêmica, em comparação com controles saudáveis. Métodos: Este estudo transversal incluiu pacientes consecutivos com infiltrados sub-epiteliais corneanos bilaterais após ceratoconjuntivite epidêmica e controles saudáveis. Foram medidas a melhor acuidade visual corrigida, uma pontuação do infiltrado sub-epitelial da córnea, a escala de graduação de Fantes e a espessura central da córnea. A histerese da córnea, o fator de resistência da córnea, a pressão intraocular correlacionada à tonometria de Goldmann e a pressão intraocular compensada da córnea foram avaliados com o Ocular Response Analyzer. Resultados: Este estudo incluiu 66 olhos de 33 pacientes com infiltrados corneanos sub-epiteliais após ceratoconjuntivite epidêmica e selecionou aleatoriamente 37 olhos de 37 voluntários saudáveis. As pontuações médias da escala de Fantes e dos infiltrados sub-epiteliais corneanos nos primeiros olhos acometidos foram respectivamente de 1,8 ± 0,8 e 2,9 ± 1,3. Nos olhos contralaterais, foram respectivamente de 1,3 ± 1,1 e 1,9 ± 1,7 (p=0,009 e p=0,002, respectivamente). O primeiro e o segundo olhos envolvidos tinham córneas significativamente mais finas (respectivamente 526,1 ± 28,1 µm; p=0,005 e 523,4 ± 38,1 µm; p=0,044) em comparação com os controles saudáveis (557,0 ± 38,1 µm). Embora a acuidade visual melhor corrigida tenha mostrado uma correlação positiva com o fator de resistência da córnea (r=0,363, p=0,045) e com a histerese da córnea (r=0,414, p=0,021), a pontuação dos infiltrados sub-epiteliais corneanos mostrou uma correlação negativa com a pressão intraocular correlacionada à tonometria de Goldmann (r=-0,479, p=0,006) e com a pressão intraocular compensada da córnea (r=-0,413, p=0,021). Conclusão: Os olhos com infiltrados corneanos sub-epiteliais tinham córneas significativamente mais finas em comparação com os controles saudáveis. Ao se medirem os valores de pressão intraocular em pacientes com infiltrados sub-epiteliais corneanos, deve-se levar em consideração tanto as correlações positivas do fator de resistência da córnea e da histerese da córnea com a melhor acuidade visual corrigida quanto as correlações negativas da pressão intraocular correlacionada à tonometria de Goldmann e da pressão intraocular compensada da córnea com a pontuação do infiltrado sub-epitelial da córnea.

Dynamic changes in and time sequence of ultraviolet B-induced apoptosis in rat corneal epithelial cells / Alterações dinâmicas na sequência temporal da apoptose induzida por radiação ultravioleta B em células epiteliais da córnea de ratos

ABSTRACT Purpose: To systematically examine the dynamic changes and time sequence in corneal epithelial cell apoptosis after excessive ultraviolet B irradiation. Methods: Ultraviolet B (144 mJ/cm2) was used to irradiate rat corneal epithelial cells for 2 h. Cell morphology was observed on differential interference contrast microscopy, and the numbers of the different kinds of apoptotic cells were counted using the ImageJ software. Cell viability was measured with the 3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2-H-tetrazolium bromide method. Cell apoptotic rate and loss of mitochondrial membrane potential were detected using flow cytometric analyses. The expression levels of 3 apoptotic genes were measured with real-time quantitative polymerase chain reaction at different time points within 0-24 h after irradiation. Results: After 144-mJ/cm2 ultraviolet B irradiation for 2 h, the expression levels of caspase-8 and Bax were highest at 0 h; furthermore, the mitochondrial membrane potential decreased at 0 h and remained constant for 6 h in a subsequent culture. At 6 h, caspase-3 was activated. The decrease in cell viability and increase in apoptotic rate peaked at 6 h. The caspase-3 expression level decreased within 12-24 h, which led to a decline in apoptotic rate and change in apoptotic stage. Conclusions: The corneal epithelial cells exhibited rapid apoptosis after ultraviolet B irradiation, which was associated with both extrinsic and intrinsic pathways.

RESUMO Objetivos: Explorar sistematicamente as mudanças dinâmicas e a sequência temporal no processo de apoptose de células epiteliais corneanas após excesso de irradiação com ultravioleta B. Métodos: A radiação ultravioleta B (144 mJ/cm2) foi utilizada para irradiar células epiteliais da córnea de rato durante 2h. A morfologia celular foi observada por meio de microscópio de contraste de interferência diferencial, e os números de diferentes tipos de células apoptóticas foram contados e registrados pelo software ImageJ. A viabilidade celular foi medida pelo método brometo de 3- (4, 5-dimetil-2-tiazolil) -2, 5-difenil-2-H-tetrazólio. A taxa apoptótica celular e a perda do potencial da membrana mitocondrial foram detectadas por meio de análises citométricas de fluxo. Os níveis de expressão de três genes apoptóticos foram medidos por reação em cadeia da polimerase quantitativa em tempo real em diferentes momentos dentro de 0-24 h após a irradiação. Resultados: Após 144 mJ/cm2 de irradiação com ultravioleta B por 2h, os níveis de expressão de caspase-8 e Bax foram maiores em 0h; o potencial da membrana mitocondrial diminuiu a 0h e permaneceu constante por 6h na cultura subsequente. Às 6h, a caspase-3 foi ativada. A diminuição da viabilidade celular e o aumento da taxa apoptótica atingiu o pico em 6h. A expressão de caspase-3 diminuiu dentro de 12 - 24 h, levando a um declínio na taxa apoptótica e alteração no estágio apoptótico. Conclusões: As células epiteliais da córnea apresentaram uma apoptose rápida após excesso de irradiação com ultravioleta B, e esse processo foi associado tanto à via extrínseca como à via intrínseca.

Clinical choice of treatment regimens for recurrent corneal erosion / 中华实验眼科杂志

Recurrent corneal erosion (RCE), a common disease caused by repeated episodes of corneal epithelial defects, is characterized by the sudden onset of eye pain, usually upon first awakening.Among many causes of the disease, trauma is the most common one, followed by epithelial basement membrane dystrophy.The disease can be diagnosed via the characteristic medical history, ocular symptoms and slit-lamp examination.Treatment of RCE includes both conservative management and surgical management.Conservative treatment is the first choice for the primary patients, including medication, bandage contact lens, application of serum drops, coverage of cryopreserved amniotic membrane, etc.The appropriate surgical procedures should be performed in patients when the conservative therapy failed.Surgical treatment mainly includes epithelial debridement, diamond burr polishing, anterior stromal puncture, alcohol delamination, phototherapeutic keratectomy, photorefractive keratectomy, femtosecond laser-assisted lamellar keratectomy, etc.RCE treatment progress was comprehensively reviewed in this article to provide references for clinical therapy.

Effects of corneal epithelium and stroma on corneal epithelial basement membrane regeneration / 中华实验眼科杂志

Basement membranes (BMs) are highly specialized extracellular matrices, which widely exist in various tissues of the human body.Since BMs were discovered in the 19th century, the structures and functions of BMs have been gradually recognized.The corneal epithelial basement membrane (EBM) participates in the regulation of corneal scar formation by limiting the activation of fibrotic factors.After an injury, the formation and duration of corneal stromal fibrosis are determined by the degree of EBM injury and the speed of EBM regeneration.Corneal epithelium and stroma participate in the process of EBM regeneration.The rapid regeneration of corneal epithelium is beneficial to the assembly of the nascent EBM.Functional corneal stromal cells provide the rest assembly components for the nascent EBM.The regular surface of corneal stroma is beneficial to the continuous regeneration of EBM, which provides positions for stromal cells.This paper reviewed the understanding of BMs, the composition and function of EBM, the relationship between corneal EBM regeneration and corneal stroma remodeling, the influencing factors of EBM regeneration and related clinical treatment methods to discuss the influence of corneal epithelium and stroma on EBM regeneration.

Differences in corneal thickness and corneal epithelial thickness measured by two kinds of frequency domain anterior segment OCT and the consistency between them / 中华实验眼科杂志

Objective:To investigate the differences in corneal thickness and corneal epithelial thickness measurements by two kinds of high-resolution frequency domain anterior segment optical coherence tomography (OCT), RTVue XR-OCT and Cirrus 5000 HD-OCT, and to analyze the consistency between them.Methods:A cross-sectional study was conducted.Fifty-two patients (52 eyes) who were admitted to Henan Eye Hospital from July to September 2019 were enrolled.The corneal thickness and corneal epithelial thickness in various areas including the central area (C area) (2-mm diameter), and 8 concentric corneal areas of 2 to 5-mm diameter, which were the superior area (S area), the superior nasal (SN area), the nasal side area (N area), the inferior nasal area (IN area), the inferior area (I area), the inferior temporal area (IT area), the temporal area (T area) and the superior temporal area (ST area) above the temporal, were measured by the same examiner using RTVue XR-OCT and Cirrus 5000 HD-OCT.The corneal thickness and corneal epithelial thickness measurements were compared to analyze the difference, correlation and consistency between the two kinds of OCT.This study adhered to the Declaration of Helsinki.The study protocol was approved by an Ethics Committee of Henan Eye Hospital (No.HNEECKY-2021[06]). Written informed consent was obtained from each subject prior to any medical examination.Results:The corneal thickness measured by RTVue XR-OCT in C, S, SN, N, IN, I, IT, T, ST areas were (521.73±29.85), (554.31±32.38), (553.54±33.30), (546.96±32.05), (537.54±32.10), (532.13±31.51), (528.42±30.38), (532.25±30.08), (544.85±30.70)μm, respectively, and the corneal thickness in the 9 areas measured by Cirrus 5000 HD-OCT were (526.77±30.62), (555.13±33.32), (558.08±32.57), (554.46±31.42), (548.29±31.84), (539.69±32.74), (536.19±32.40), (533.38±31.90), (543.83±32.02)μm, respectively.There was no significant difference in corneal thickness of various areas between the two kinds of OCT (all at P>0.05), and there were positive correlations between them ( r=0.99, 0.89, 0.95, 0.97, 0.95, 0.93, 0.96, 0.97, 0.92; all at P<0.01). Bland-Altman analysis showed that there was a good consistency of corneal thickness measurements by the two kinds of OCT.The corneal epithelial thickness in C, S, SN, N, IN, I, IT, T, ST areas measured by RTVue XR-OCT were (52.06±3.26), (52.58±3.48), (53.06±3.56), (53.75±3.49), (53.81±3.40), (53.48±3.35), (52.96±3.32), (52.67±3.19), (53.12±3.15) μm, respectively, and the corneal epithelial thickness in the 9 areas measured by Cirrus 5000 HD-OCT were (46.75±3.25), (47.40±3.36), (47.58±3.64), (48.85±4.48), (48.46±4.54), (48.40±4.96), (48.06±5.12), (47.46±3.91), (48.79±3.90)μm, respectively.There were statistically significant differences in the corneal epithelial thickness of various areas measured by the two kinds of OCT (all at P<0.05), and there was no significant correlation between them ( r=0.17, 0.08, 0.16, 0.28, 0.20, 0.24, 0.19, 0.21, 0.13; all at P>0.05). Bland-Altman analysis showed poor consistency of corneal epithelial thickness measurements between the two kinds of OCT. Conclusions:There is no significant difference in measuring corneal thickness between the two kinds of OCT and the consistency is high, which means that they can be replaced by each other.There are significant differences in corneal epithelial thickness measurement between them and the consistency is poor, so they are not interchangeable.

Severe corneal burn due to the accidental application of salicylic acid packed in a plastic dropper bottle / Quemadura corneal grave debida a la aplicación accidental de ácido salicílico envasado en un frasco gotero plástico

Eye burns due to the accidental application of pharmacological or nonpharmacological substances packaged in plastic dropper bottles have been described for more than three decades and continue to occur. These burns can cause potentially serious corneal injuries. We report the case of a patient who mistakenly applied salicylic acid to the right eye after confusing it with an eye lubricant, which caused him a severe corneal burn. Fortunately, after aggressive medical and surgical management (including oxygen therapy and amniotic membrane grafting), the visual results were good. We suggest conducting educational campaigns and taking legislative measures in our country to avoid packaging corrosive substances in this type of dropper bottle to reduce the risk of accidental burns.

Las quemaduras oculares por aplicación accidental de sustancias farmacológicas o no farmacológicas envasadas en frascos goteros plásticos, se han descrito desde hace más de tres décadas y siguen ocurriendo. Estas quemaduras pueden causar lesiones potencialmente graves de la córnea. Se presenta el caso de un paciente que se aplicó ácido salicílico en el ojo derecho al confundir el envase con el de un lubricante ocular, lo que le causó una grave quemadura corneal. Afortunadamente, tras un manejo médico y quirúrgico agresivo (incluida oxigenoterapia e injerto de membrana amniótica) los resultados visuales fueron buenos. Se sugiere hacer campañas educativas y adoptar normas en el país para evitar el envase de sustancias corrosivas en este tipo de frascos goteros, con el fin de disminuir el riesgo de quemaduras accidentales.

Application effect of bandage corneal contact lens in ptosis during surgical treatment / 中国基层医药

Objective To study the application effect of bandage corneal contact lens in ptosis during surgical treatment.Methods A total of 62 patients(73 eyes) with primary congenital ptosis in the First People's Hospital of Xiantao from March 2013 to March 2016 were randomly divided into group A,group B and group C.All of the three groups were treated by shortening levator palpebrae superioris muscle.The A group[20 cases(24 eyes)] began to wear bandage corneal contact lens during the operation.The B group [22 cases (25 eyes)] began to wear bandage corneal contact lens at the end of surgery.And the C group [20 cases (24 eyes)] took conventional methods for covering operative eyes.Postoperative follow-up lasted for 3 months,the postoperative FL staining scores and ocular pain severity were compared among the three groups.Results Comparison of postoperative FL staining scores:there was no statistically significant difference between B group and C group at postoperative 1 day(q =0.537,P ＞ 0.05),but the differences between B group and A group were statistically significant (q =10.876,11.298,all P ＜ 0.05),the differences among the three groups were statistically significant at the 7th day after surgery (q =8.682,4.048,4.722,all P ＜ 0.05).There was no statistically significant difference between B group and A group at postoperative 2 weeks (q =1.635,P ＞ 0.05),but the differences between group A/B and group C were statistically significant (q =8.747,7.201,all P ＜ 0.05).There were no statistically significant differences among the three groups at postoperative 3 months (q =1.607,0.186,1.438,all P ＞ 0.05).Comparison of postoperative ocular pain severity:there were no statistically significant differences among the three groups at postoperative 1 day (q =0.986,0.586,0.410,all P ＞ 0.05).At postoperative 7 days,there was no statistically significant difference between A group and B group (q =0.948,P ＞ 0.05),but the differences between A/B group and C group were statistically significant (q =4.743,3.843,all P ＜ 0.05).There were no statistically significant differences among the three groups at postoperative 1 month (q =3.181,0.599,2.654,all P ＞ 0.05).Postoperative upper eyelid radian and double eyelid plasty in all of 62 cases(73 eyes) was satisfied and the width of palpebral fissure when look straight was normal and locating above superior margin of pupil,but there were 16 eyes with slightly hypophasis which were all naturally closed good after 1 to 2 months without surgical incision infection and corneal infection.Conclusion It is effective to protect the cornea since intraoperative application of bandage corneal contact lens,and it with high safety to wear corneal contact lens shortly after surgery,which can promote corneal epithelial wound healing,reducing incidence of exposure keratitis,at the same time,it can obviously relieve ocular pain in patients.

Effect of the bioprotectant agent trehalose on corneal epithelial healing after corneal cross-linking for keratoconus / Efeito do agente bioprotetor trealose na cicatrização epitelial da córnea após reticulação corneana para ceratocone

ABSTRACT Purpose: This study aimed to compare the effectiveness of eye drops containing a combination of sodium hyaluronate and trehalose and sodium hyaluronate for the treatment of corneal cross-linking and epithelial healing. Methods: This study included 46 eyes of 23 keratoconus patients who underwent corneal cross-linking on both eyes. Unpreserved trehalose 30 mg/mL and sodium hyaluronate 1.5 mg/mL (Thealoz Duo®; Thea, France) were applied six times a day on one eye of each patient and unpreserved sodium hyaluronate 0.15% (Eye Still®; Teka, Inc., Istanbul) was applied on the other eye. Patients were examined daily until complete re-epithelialization. Postoperative examinations to assess the measured size of epithelial defect were performed using slit-lamp biomicroscopy. Results: The study included 23 patients (13 females and 10 males) with a mean age of 20.9 ± 10.3 years. Corneal epithelial healing time after cross-linking was 2.3 ± 1.2 days for the trehalose and sodium hyaluronate group and 3.8 ± 2.9 days for the sodium hyaluronate group (p=0.03). Conclusion: The application of eye drops containing the combination of trehalose and sodium hyaluronate resulted in faster corneal re-epithelialization following corneal cross-linking than that of eye drops containing sodium hyaluronate alone.

RESUMO Objetivo: Este estudo teve como objetivo comparar a eficácia de colírios contendo uma combinação de hialurônico de sódio e hialuronato de sódio e trealose para o tratamento da cicatrização epitelial em pacientes com cross-linking corneano. Métodos: Este estudo inclui 46 olhos de 23 pacientes com ceratocone, que foram operados com cross-linking corneano em ambos os olhos. Trealose não preservada 30 mg/mL e hialuronato de sódio 1,5 mg/mL (Thealoz Duo®; Thea, França) foram aplicados seis vezes por dia em um olho de cada paciente e hialuronato de sódio não conservado, 0,15% (Eye Still®; Teka, Inc., Istambul) foi aplicada no outro olho. Os pacientes foram examinados diariamente até a completa reepitelização. Exames pós-operatórios para avaliar o tamanho medido do defeito epitelial foram realizados usando biomicroscopia com lâmpada de fenda. Resultados: O estudo incluiu 23 pacientes (13 mulheres e 10 homens) com idade média de 20,9 ± 10,3. O tempo de cicatrização epitelial da córnea após o cross-linking foi de 2,3 ± 1,2 dias para o grupo trealose e hialuronato de sódio e 3,8 ± 2,9 dias para o grupo hialurônico de sódio (p=0,03). Conclusão: A aplicação de gotas para os olhos contendo combinação de trealose e hialuronato de sódio resultou em uma re-epitelização da córnea mais rápida após o cross-linking corneano do que a de gotas contendo hialurônico de sódio apenas.

Risk factor analysis of persistent corneal epithelial defects after vitrectomy in patients with proliferative diabetic retinopathy / 中华眼底病杂志

Objective To analyze the risk factors for persistent corneal epithelial defects (PCED) after pars plana vitrectomy (PPV) in patients with proliferative diabetic retinopathy (PDR).Methods A total of 201 PDR patients (201 eyes) who received PPV were enrolled in this retrospective study.There were 86 males (86 eyes) and 115 females (115 eyes).The patients aged from 30 to 81 years,with the mean age of (57.94±9.65) years.Among them,159 patients were ≥50 years of age,and 42 patients were ＜50 years of age.There were 36 patients with HbA1c ＜7.0％,165 patients with HbA1c ≥7.0％.There were 93 right eyes and 108 left eyes.There were 93 right eyes and 108 left eyes.The diabetic retinopathy stages were as follows:stage Ⅳ in 24 eyes,stage Ⅴ in 78 eyes and stage Ⅵ in 99 eyes.The operation time was ranged from 1 to 4 hours,with an average of 2 hours.Among the 201 eyes,corneal epidermis were scraped on 25 eyes;70 eyes were combined with cataract surgery;a laser photocoagulation count ＜ 1000 points was performed in 78 eyes,and ＞ 1000 points were performed in 123 eyes.Sixty-one eyes involved intravitreal silicone oil tamponade,18 eyes involved intravitreal tamponade with C3F8,and 122 eyes were not involved with intraocular tamponade.Postoperative persistent intraocular hypertension was defined as an intraocular pressure (IOP) ≥21 mmHg (1 mmHg=0.133 kPa) after PPV with necessary treatment using IOP-lowering medications for ≥ 2 weeks.The diagnostic criteria for corneal epithelial defects were taken from the Expert Consensus on Clinical Diagnosis and Treatment of Corneal Epithelial Defect in China (2016).The corneal epithelial defect was diagnosed as PCED if it was treated with common methods such as a lacrimal substitute or corneal contact lens,but showed no improvement and no signs of healing for ≥2 weeks.The incidence of PCED after eye surgery was recorded and its related risk factors were analyzed.A multivariate logistic regression was used to analyze the risk factors for PCED,which were expressed as a odds ratio (OR) and a 95％ confidence interval (CI).Results Of 201 eyes,16 eyes (7.96％) presented with PCED after surgery and 185 eyes (92.04％) with no PCED.There was no significant difference in the age,sex,and eyes between the patients with or without PCED (x2=6.548,0.927,0.044;P=0.011,0.336,0.833).A multivariate logistic regression showed that intraoperative epithelial debridement (OR=1 3.239,95％CI 2.999-58.442,P=0.001),intraoperative treatment in combination with cataract surgery (OR=7.448,95％CI 1.975-28.091,P=0.003),intravitreal tamponade with C3F8 (OR=11.344,95％CI 2.169-59.324,P=0.004),and postoperative persistent intraocular hypertension (OR=10.462,95％CI 2.464-44.414,P=0.001) were risk factors for PCED after PPV.Conclusion Intraoperative epithelial debridement,intraoperative treatment in combination with cataract surgery,intravitreal tamponade with C3F8,and postoperative persistent intraocular hypertension are risk factors for PCED in patients with PDR after PPV.

A supramolecular look at microenvironmental regulation of limbal epithelial stem cells and the differentiation of their progeny / Uma visão supramolecular sobre a regulação microambiental de células tronco epiteliais limbais e a diferenciação de sua progênie

ABSTRACT Various approaches have been taken to improve our knowledge of the microenvironmental regulation of limbal epithelial stem cells. Researchers have extensively investigated the roles of growth factors, survival factors, cytokines, enzymes, and permeable molecules secreted by the limbal cells. However, recent evidence suggests that stem cell fate (i.e., self-renewal or differentiation) can also be influenced by biophysical and mechanical cues related to the supramolecular organization and the liquid crystalline (mesophase) nature of the stromal extracellular matrix. These cues can be sensed by stem cells and transduced into intracellular biochemical and functional responses, a process known as mechanotransduction. The objective of this review is to offer perspectives on the supramolecular microenvironmental regulation of limbal epithelial stem cells and the differentiation of their progeny.

RESUMO Muitas abordagens têm sido utilizadas para ampliar entendimentos sobre a regulação microambiental das células tronco epiteliais limbais. Neste contexto, pesquisadores têm exaustivamente investigado a participação de fatores de crescimento, fatores de sobrevida, citocinas, enzimas e moléculas permeáveis secretadas pelas células limbais. Entretanto, evidências recentes sugerem que o destino (ie. autorrenovação ou recrutamento para a via de diferenciação) das células tronco também sofre influência de estímulos biofísicos ou mecânicos relacionados à organização supramolecular e à natureza liquido-cristalina (mesofases) da matriz extracelular estromal. Esses estímulos podem ser percebidos e traduzidos pelas células tronco em sinais bioquímicos que geram respostas funcionais, através de um processo designado de mecanotransdução. Objetiva-se, com a presente revisão, oferecer ao leitor perspectivas supramoleculares sobre a regulação microambiental das células tronco epiteliais limbais e a diferenciação de sua progênie.

Protective effects of thymosin β4 on ethanol-induced rabbit corneal epithelial cell damage in vitro / 中华实验眼科杂志

Background Laser assisted subepithelial keratomileusis (LASEK) is one of surgical procedures for refractive correction.Dilute alcohol that is used for the removal of epithelium during LASEK induces the apoptosis of corneal epithelial cells.Researches showed that thymosin β4 (Tβ4) can arrest apoptosis, but whether Tβ4 plays inhibitory effect on ethanol-induced damage of corneal epithelial cells is still unelucidated.Objective The aim of this study was to investigate the protective effects of Tβ4 on ethanol-induced rabbit corneal epithelial cell damage in vitro.Methods The corneal tissue of deendothelium was obtained from 10 New Zealand white rabbits.Corneal epithelial cells were cultured in vitro by using explant culture method.Cultured cells were identified by detecting the expression of keratin 12 and connexin 43 with reverse transcription PCR (RT-PCR).The cells of second generation were collected and divided into 4 groups.The cells were regularly cultured in the normal control group, and Tβ4 was added in the culture medium at the final concentration of 1 μg/ml in the Tβ4 treated group.Ethanol-induced rabbit corneal epithelial cell damage models were established by adding PBS containing 20％ alcohol in medium for 20 seconds in the model group,and Tβ4 was added in the medium of model cells at the final concentration of 1 μg/ml in the model+Tβ4 group.The survival rate of the cells was detected by MTT assay, and the apoptosis rate of the cells was examined by TUNEL method.The relative expression levels of cyclin D1 mRNA and cyclin-depensent protein kanase 4 (CDK4) mRNA in the cells were detected by real-time flurescenee quantitative PCR.The content of bcl-2 protein in the cells was detected by ELISA assay.Spectrophotometry was employed to measure the activity of caspase-3.The study complied with the Regulation for the Adminstration of Affairs Concerning Experimental Animals by State Science and Technology Commission.Results The mean cell survival rate was (52.1 ± 14.07) ％ in the model group,which was significantly reduced in comparison with 100％ of the normal control group and (77.7± 19.60) ％ of the model+Tβ4 group (P=0.001 ,P=0.035).TUNEL staining revealed more positive cells in the model group and the model+Tβ4 group,and the percentage of TUNEL positive cells was (30.0±6.7)％ in the model+Tβ4 group, showing an evident decline in comparison with (42.4±4.0)％ of the model group (P=0.01).The relative expression levels of cyclin D1 mRNA and CDK4 mRNA were 0.93±0.17 and 0.88±0.09 in the model+Tβ4 group, which were significantly higher than 0.68±0.05 and 0.54±0.07 in the model group (P=0.027,0.002).ELISA assay exhibited that bcl-2 content in the cells was considerably lower,and caspase-3 activity was significantly higher in the model group than those in the model+Tβ4 group (P =0.030,0.021).Conclusions Tβ4 plays a protective effect on rabbit corneal epithelial cells from apoptosis by lowing the caspase 3 activity and increasing bcl-2 content in ethanoldamaged rabbit corneal epithelial cells.In addition, Tβ4 promotes the regrowth of corneal epithelial cells by upregulating the expression of cyclin D1 and CDK4.

Feasibility of bacterial cellulose membrane as biological scaffold for construction of tissue engineering corneal epithelium / 中华实验眼科杂志

Background Corneal transplantation is a primary method for the treatment of serious corneal diseases, but its application is limited because of the shortage of corneal donor.The study on tissue engineering corneal epithelium provides a new approach to corneal transplantation, and the biological scaffold materials for tissue engineering corneal epithelium is an issue of increasing concern.Bacterial cellulose membrane has been used in medical field,but its application in tissue engineering corneal epithelium deserves more researching.Objective This study was to evaluate the biocompatibility of bacterial cellulose membrane as a biological scaffold of tissue engineering corneal epithelium.Methods Corneal epithelium was isolated from 1 month-old New Zealand White rabbit.Corneal epithelial cells were cultured using explant method and identified by detecting the CK-3 expression using immunofluorescence technique.The second generation ceils were inoculated on bacterial cellulose membrane and culture plate, respectively, and the growth status of the cells were examined and compared under the optical microscope.The cell activity/toxicity test was performed by LIVE/DEAD cell staining kit at the third day after inoculation to evaluate the survival rate.The ultrastructure of the cell surface was examined under the scanning electron microscope.The study was performed in accordance with the ARVO Statement.Results Rabbit corneal epithelial cells grew well 1 week after primarily cultured with a cobblestone-like appearance and positive response for CK3 antibody.The cells on the bacterial cellulose membrane presented a round shape and regular arrangement and showed the green fluorescence for LIVE/DEAD test,with the survival rate 100％.Abundant leafy protrusion, microvilli and intercellular junction were seen under the scanning electron microscope.In addition, mitosis phase of cells and many filopodia between the cells and bacterial cellulose membrane were also exhibited.Conclusions Rabbit corneal epithelial cells can grow well in bacterial cellulose membrane.Bacterial cellulose membrane has good biocompatibility, indicating that bacterial cellulose membrane can be used as new biological material for tissue engineering corneal epithelium.

Localized flap melt after Nd-YAG laser treatment in recurrent post-LASIK epithelial ingrowth / Derretimento localizado de flap após o tratamento por Nd-YAG laser para crescimento epitelial recorrente pós-LASIK

ABSTRACTNeodymium: Yttrium-Aluminum-Garnet (Nd-YAG) laser treatment of epithelial ingrowth was found promising with high success rates in cases of primary post-LASIK epithelial ingrowth. However, the application range of this procedure is not well-known. For the first time, the authors report the outcome of a patient treated with Nd-YAG laser for multiple recurrences of post-laser in situ keratomileusis epithelial ingrowth.

RESUMOO tratamento com laser de neodímio: Ítrio-Alumínio-Granada (do inglês, Nd-YAG Laser) para o crescimento epitelial primário pós-LASIK demonstrou altas taxas de sucesso. No entanto, os limites deste procedimento não são completamente conhecidos. Pela primeira vez, os autores relatam os resultados de um olho tratado com Nd-YAG laser para múltiplo crescimento epitelial pós-LASIK recorrente que desenvolveu um derretimento localizado do flap.

Construction of tissue-engineered corneal epithelium by culturing human amniotic mesenchymal stem cells in vitro / 中华实验眼科杂志

Background Corneal transplantation is an effective treatment to severe corneal diseases,but the shortage of cornea donor limits its application.Tissue-engineered cornea is being a new approach to corneal diseases.Objective This study was to investigate the possibility of construction of tissue-engineered corneal epithelium by culturing human amniotic mesenchymal stem cells (hAMSCs) in vitro.Methods Fresh human amniotic membranes were obtained under the approval of Ethic Committee of Affiliated First Hospital of Jinan University and informed consent of maternal women.The 6 cm×6 cm amniotic membrane tissue explant was digested using trypsin+ EDTA,and then the amniotic epithelial cells (AECs) were scraped before putting into collagenase Ⅱ digestion medium to isolate hAMSCs.hAMSCs of passage 3 were cultured to achive 80％-90％ confluence,and then the ceils were incubated on rabbit deepithelial corneal stroma at a 1 ×105/ml density.The corneal stroma was co-cuhured with hAMSCs at an air-liquid interface till 14 days.Rabbit deepithelial corneal stroma with and without hAMSCs (experimental group and control group) were fixed in 4％ para formaldehyde, and sections were prepared for histopathological examination.Immunochemistry and immunofluorescence were empoyed to detect the expressions of cytokeratin3 (CK3) and CK12 in hAMSCs.Results hAMSCs grew well and formed a stratified epidermal structure resembling native corneal epithelium on rabbit corneal stroma in cultured 14 days in the experimental group,with the oval nucleus at basement and fusiform nucleus on the surface of corneal stroma.There was no cell structure in the control group.Immunochemistry revealed brown staining for CK3, CK12 in cytoplasm of hAMSCs on the rabbits corneal stroma,and the green fluorescence for CK3 and CK12 was also seen in the hAMSCs.However,the response for CK3 and CK12 was absent in the control sections either immunochemistry or immunofluorescence test.Conclusions hAMSCs can be induced to differentiate into corneal epithelioid cells at an air-liquid interface on the rabbit corneal stroma.

Pay more attentions to the complexity of the resident immune cells in ocular surface / 中华实验眼科杂志

Ocular surface is a special interface between the inner ocular tissue and the external environment.It provides effective physical and biological barriers to prevent environmentally harmful substances and pathogenic microbes invading into the eye.This protection is afforded by unique local anatomy and cellular components, especially the resident immune cells such as innate lymphoid cells (ILCs), macrophages, mast cells, Langerhans cells(LCs) and γδ T cells.Recent studies reinforce the importance of LCs and mast cells as inducers of immune tolerance.Most adult tissue macrophage populations are seeded before birth and maintained in the steady state independently of monocytes from blood.However, under inflammatory condition, some transient monocytes enter into tissue and become macrophage compartments.Monocytes are subdivided into two main phenotypically and functionally distinct subsets.The first main subset is dedicated to the surveillance of endothelial integrity.The second main subset compasses classical monocyte functions such as rapid migration to the sites of injury and the replenishment of peripheral dendritic cells and macrophage compartments.In addition, newly identified ILCs are founded in the ocular surface tissues.These cell groups defens the different stimulus from external environment by producing different cytokines and growth factors.Accumulating data highlight some key roles of tissue-resident immune cells in ocular surface homeostasis and pathology.

Current researches of tissue engineering corneal epithelium seed cells / 中华实验眼科杂志

Keratoplasty is a choice for the treatment of ocular surface diseases caused by corneal limbal stem cells (LSCs) deficiency.The application of traditional keratoplasty is limited by avaibility of donor corneas and allograft rejection.Constructruction of tissue engineering corneal epithelium provides an important and effective approach to the transplantation of cornea,because it can solve the lack of donor corneas and avoid allograft rejection following keratoplasty.However,the selection of the seed cells is crucial to corneal tissue engineering.What is more,the research of seed cells is becoming more and more widespread,just like embryonic stem cells (ESCs) and LSCs.This article summarized the selection of seed cells and the progress of tissue-engineered human corneal epithelium.

Retrospective analysis of clinical features and management for drug-induced keratopathy / 中华实验眼科杂志

Background In recent years,incidence of drug-induced keratopathy is increasing highly.Druginduced keratopathy is lack of typical clinical features and offen confused with the primary disease.Therefore,summarizing and concluding the clinicals feature and standard treatments of drug-induced keratopathy are key problem need to be solved urgently for us.Objective This study was to retrospectively analyze the clinical features and therapeutic procedure of drug-induced keratopathy.Methods A retrospective case series analysis method was adopted.The clinical data of 36 eyes (31 patients) with drug-induced keratopathy were collected by Shandong Eye Hospital from 2008 to 2012,including eye disease history,medication history,medication dosage and duration.A series of relevant examinations were performed,including best corrected visual acuity (BCVA) before and 1 month after treatment,Schirmer test Ⅰ (S Ⅰ t),tear film break-up time (BUT),meibomian gland findings,the location of the keratopathy,the characteristics of keratophthy before and after fluorescein staining.The treating were given,including cessating of the original drugs,applying corneal repair promotion and anti-inflammatory drugs as well as the comprehensive treatment for meibomian gland embolization and dry eye,such as the hot packs and massage in the eyes with meibomian gland dysfunction and a tear dot embolization therapy in the eyes with S Ⅰ t ＜ 5 mm and BUT＜5 s.Paired t test and repeated measured one-way analysis of variance in SPSS 17.0 software were used to compare the BCVA,BUT and S Ⅰ t outcomes.The correlation between corneal repair duration and S Ⅰ t results was analyzed by Pearson linear correlation analysis.Results The primary cause of drug-induced keratopathy was irrational use of drugs,including antiviral drugs,antibiotics,hormone,antiallergic,lowering-intraocular pressure drugs,turn for 23 eyes,12 eyes,10 eyes,1 eye and 1 eye,respectively.Improper route of administration included 25 cases of overuse of eye drops and 6 cases of subconjunctival injection.BCVA was 0.69 ± 0.28 1 month after treatment,which was significantly improved in comparison with before treatment (0.32 ± 0.26) (t =11.02,P ＜ 0.01).Clinical manifestations included corneal epithelial diffusive and point-like roughness,corneal epithelial defect and even corneal ulcer for severe cases,corneal edema,Descemet membrane folds and partially visible corneal filiform.Drug-induced keratophthy was mainly located in the central and lower cornea.Comprehensive therapy was effective with the treating duration about 1 week to 8 weeks.A negative correlation was found between the corneal restore duration and S Ⅰ t results (r =-0.835,P＜0.01).Conclusions Corneal changes secondary to topical medications may affect all layers of the cornea.Clinicians should be mindful of drug-induced ocular disorders.The early diagnosis of druginduced keratopahthy depends on the medical history and clinical features.A comprehensive treating based on ocular surface conditions is available.

Location of corneal epithelial stem cells under in vivo and in vitro conditions / 中国组织工程研究

BACKGROUND:There are two types of epithelial stem cells in the ocular surface tissue:corneal epithelial stem cells and conjunctival epithelial stem cells. The corneal epithelial stem cells play an important role in renewal of corneal epithelial cells and maintenance of corneal transparency. OBJECTIVE:To study the location of corneal epithelial stem cells using laser in vivo confocal microscopy and immunofluorescent staining. METHODS:Patients with unilateral limbal stem celldeficiency who went to Henan Eye Institute from September 2009 to September 2012 were enrol ed in this study. Bilateral eyes were scanned by laser in vivo confocal microscopy, and the healthy eye was imaged as a control. The central cornea and limbus were scanned and images were recorded for statistical analysis. The eye bal s were obtained from Henan Eye Bank, China. Central cornea and limbus were dissected and embedded in the OCT compound for frozen section and the proper thickness of the section was 5-7μm. Immunofluorescent staining was used to detect the expression of p63, ABCG2, K3 and Connexin 43 in the epithelial layers of central cornea and limbus. RESULTS AND CONCLUSION:Twenty-four patients diagnosed with unilateral limbal stem celldeficiency were recruited. Under confocal microscopy, in the affected eyes, the typical morphology of conjunctival epithelial cells and goblet cells was detected instead of corneal epithelial cells;in the limbus, a great amount of fiber scarring tissue was detected instead of Vogt palisade, rete pegs and pigment cells. Immunofluorescent staining showed the expression of p63, ABCG2 was mainly in the basal layer of limbal epithelium, especial y in the outer and middle parts, but the expression of p63 and ABCG2 was not detected in the epithelial celllayers of central cornea. K3 and Connexin43 were not expressed in suprabasal layers of limbal epithelium, but in central cornea, they were expressed highly in the whole epithelial celllayers. Laser in vivo confocal microscopy and immunofluorescent staining showed the corneal epithelial stem cells were located in the basal layer of outer and middle limbal epithelium, mainly in Vogt palisade and rete pegs.

Tempo de reepitelização corneana com a instilação de colírio contendo hialuronato de sódio e carboximetilcelulose / Corneal reepithelialization time with instillation of eye drops containing sodium hyaluronate and carboxymethylcellulose

OBJETIVO: Avaliar o tempo de reepitelização corneana pós abrasão usando colírios comercialmente disponíveis, um contendo hialuronato de sódio a 0,4%, outro contendo carboximetilcelulose a 1%, e comparar com a reepitelização sem instilação de colírio. MÉTODOS: Foram utilizados 24 coelhos, nos quais foi feita a abrasão mecânica da córnea nos 8 mm centrais. Esses animais foram divididos em três grupos. O primeiro grupo recebeu um colírio disponível comercialmente contendo hialuronato de sódio 0,4%, o segundo recebeu um colírio contendo carboximetilcelulose 1% e o terceiro não recebeu nenhuma droga. A avaliação foi feita a cada 24 horas por meio da análise de fotografias digitais sob luz azul de cobalto e coramento das córneas com fluoresceína a 2%. O estudo das imagens foi feito pelo sistema de análise de imagens do Autocad 2009®. A análise dos dados foi feita comparando o tempo total de reepitelização da córnea e a cada 24 horas entre os três grupos. RESULTADOS: A velocidade de reepitelização do grupo que usou colírio contendo hialuronato de sódio foi em média 90 horas; o grupo que usou carboximetilcelulose apresentou média de 105 horas; e o grupo que não usou nenhum tipo de lubrificante apresentou média de 108 horas para total reepitelização. Houve uma melhor performance na reepitelização após 96 horas nas córneas dos coelhos que usaram os colírios lubrificantes, sendo essa diferença estatisticamente comprovada. CONCLUSÃO: O colírio contendo hialuronato de sódio 0,4% mostrou índice de eficácia maior que aquele contendo carboximetilcelulose 1%, e este maior eficácia que o controle. Os resultados encontrados neste estudo mostram que o uso de lubrificantes no processo de reepitelização são de extrema valia e devem ser usados de rotina na clínica oftalmológica.

PURPOSE: Evaluate the time of post-abrasion corneal re-epithelialization using commercially available eye drops, one of which containing 0.4% sodium hialuronate, and the other containing 1% carboxymethylcellulose, and compare them to the re-epithelialization without the drops. METHODS: 24 rabbits were used, which had the mechanical abrasion of the central 8 mm of their corneas done. These animals were divided in 3 groups. The first one received the drops containing 0.4% of sodium hialuronate, the second one received the drops containing 1% of carboxymethylcellulose and the third group did not receive any drugs. The evaluations took place every 24 hours through the analysis of digital pictures under cobalt blue light and coloring of the corneas with 2% fluorescein. The pictures were analyzed with the software Autocad 2009®. The data was analyzed through the comparison of the total re-epithelialization time among the three groups RESULTS: The time of total re-epithelialization of the group using sodium hialuronate was on average 90 hours and the group using carboxymethylcellulose 105 hours, while the group using no drugs was 108 hours. There was a better performance of those groups using the drops and this difference can be proved statistically. CONCLUSION: The drops containing 0.4% of sodium hialuronate showed a higher efficiency rate compared to the drops containing 1% of carboxymethylcellulose, which was higher than the control group. The results of the present study show that the use of lubricants in the process of re-epithelialization are extremely valid and must be used frequently in ophthalmologic clinic.